7 glue sticks cost $6.37. Which equation would help determine the cost of 6 glue sticks?
Explanation: There are several equations that could help determine the cost, each with a slightly different approach. We can write the fact that 7 glue sticks cost $6.37 as a proportion: $\dfrac{7}{\$6.37}$ Let $x$ represent the unknown cost of 6 glue sticks. Since 6 glue sticks cost $x$ , we have the following proportion: $\dfrac{6}{x}$ The cost changes along with the number of glue sticks purchased, and so the two proportions are equivalent. $\dfrac{7}{\$6.37} = \dfrac{6}{x}$